Heteroepitaxial growth of vertical GaAs nanowires on Si(111) substrates by metal-organic chemical vapor deposition.
Epitaxial growth of vertical GaAs nanowires on Si(111) substrates is demonstrated by metal-organic chemical vapor deposition via a vapor-liquid-solid growth mechanism. Systematic experiments indicate that substrate pretreatment, pregrowth alloying temperature, and growth temperature are all crucial to vertical epitaxial growth. Nanowire growth rate and morphology can be well controlled by the growth temperature, the metal-organic precursor molar fraction, and the molar V/III ratio. The as-grown GaAs nanowires have a predominantly zinc-blende crystal structure along a <111> direction. Crystallographic {111} stacking faults found perpendicular to the growth axis could be almost eliminated via growth at high V/III ratio and low temperature. Single nanowire field effect transistors based on unintentionally doped GaAs nanowires were fabricated and found to display a strong effect of surface states on their transport properties.
Bao
Xin-Yu
XY
Department of Electrical and Computer Engineering, University of California San Diego, La Jolla, California 92093-0407, USA.
Soci
Cesare
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Susac
Darija
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Bratvold
Jon
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Aplin
David P R
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Wei
Wei
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Chen
Ching-Yang
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Dayeh
Shadi A
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Kavanagh
Karen L
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Wang
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